I've backed a LOT on Kickstarter. At least a dozen games, almost a dozen board games, a book, some tech projects, etc.
Playtonic's communication frequency is par for the course. A few updates here, a few there. Their communication quality is top notch. Very few developers give you truthful, concise insight into the progress and difficulties of the project. Even fewer give insight into the evolution of the team.
But what actually matters is their product is going to be FINISHED. Of the dozen games I've backed, one has been in development for over 6 years and I can't play it because I only want to play the finished game (hi Star Citizen), one is in whatever-beta-limbo-land (Timber & Stone), one swears it's still being worked on but has never once shown progress (Unsung Story), and several were flat out canceled with no refunds.
Kingdom Death: Monster gave out a TON of updates until the day the Kickstarter ended and then has been silently working since, but again, this is normal.
I think people dramatically underestimate the work that it requires to bring a Kickstarter to completion. You have to first make a product which is ridiculously hard in and of itself. Then make all the supplementary materials (rule books, manuals, boxes, discs in this case, art, etc). Then make all the gifts if there are any (this game had tons). Then handle production which usually requires several manufacturing plants, gather everything, pack it correctly, pack the packed things into a box to ship, and finally distribute it. It's a massive undertaking. I don't think there's a ton of time to update every single person's every single question, because that's wasted time that could be used on the project.
Playtonic is finishing the game. That's more than MOST Kickstarters can say, and that's all they owe anyone.
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